Correct me if I'm wrong. I thought that the XP-7 is in the same league as the PPA. The pocket reference is definitely inferior (according to Larry) than the PPA? Will this be a good comparison, sound wise?

[size=large]Someone has said (I think it was Extreme, but I may be wrong) that the competition for the PPL PR was the Ray Samuels XP7. The PR is actually a bit more compact than the XP7, although the XP7 seems to be a bit more battery efficient. At the recent Seattle meet, the PPL PPA was actually being compared with the HR Blockhead! [/size]

[size=large]Well, that is the very point: I am talking about the comparisons between PPL's maxed out PPA and the blockhead - not the typical PPA. This should place it above the XP7. (I am only talking about PPL's maxed out units here. This very thread is about a maxed out PR.)

PPL's maxed out PR also utilizes the diamond buffer and up to four stacked diamond buffers at that (see http://laroccoaudio.com/Pocket-Reference.htm). This should at least place it in the XP7's league. I just want to get a feel for how close.[/size]

[size=large]You're telling me! Everytime I get ready to pull the trigger on an amp, something new keeps coming out to give me pause. I have also been struggling somewhat financially at times, although things appear to be looking up lately.

Well, I can delay only so long. I will be soon choosing an audiophile portable amp and will later choose a audiophile home amp, which will have to be better! than the portable one. I will most likely pick up some Etys before I get either amp - after all, what's the point in getting all this sonic beauty without some high-end phones to appreciate them? [/size]

Thanks for the correction, b/c the triad module (diamond buffer) sure won't fit in the PR.

Jap,

You really have to look hard at your budget. If portability is your main concern, why not get the PI-META? Then save more money and get the maxed out PPA. The PR with Maxed Out PPA will cost you about 1K, while the portable PI-META and Maxed Out PPA will save you at least 250 bucks. To me, portable application is much less critical in comparison to home application factoring noise...and such.

Ety4s is the best way for portable phones, if you have no problem with the ergonomics. Although, I love the sound of the ETY4s..I can't stand having something stick into my ears that deep!

[size=large]Grinch,
the BUF634-P Open Loop Buffer was referred to as "a diamond buffer on a chip" (from the 2nd paragraph of the link I provided above). Whether this is a reduced version of the Ultra Linear Discrete Diamond Buffer I do not know.

Purk,
I rather save and get a quality product than accept a compromise. Portability AND quality are my main concerns. Besides, the type of portability I am concerned with is transportability. I have no intention on getting run over by a vehicle while groovin' with Ety's or any other closed phones. I use my portable system in work environments, at libraries, even in church before services.

I know I can deal with the Etys because I have worked in an oil refinery as an engineering assistant and would wear ear plugs, both hard or foam, for hours at times. I tested the Etys at the Chicago meet last October, and that testing eliminated the Ultrasone 650 TrackMasters and the AKG 271's as viable closed phone alternatives for me. The Etys simply blew them away for my needs sincce I favor detail and musicality. Currently, I am using the Senn PX200's as an acceptable cheap alternative until I lay down the green for the Ety's. PX200's will also come in handy for those times when the Ety's isolation is problematic, like when I need to hear a phone ring. I will probably go for the more neutral ER-4B's.[/size]

The PR has no differential output. The PIMETA has no opamp power rail isolation, and has a congested layout due to size constraints. So both are missing part of the PPA circuit. It would be interesting to do some A-B listening tests.

Diamonds

Quote:

Originally posted by Jap[...] the BUF634-P Open Loop Buffer was referred to as "a diamond buffer on a chip" (from the 2nd paragraph of the link I provided above). Whether this is a reduced version of the Ultra Linear Discrete Diamond Buffer I do not know.[...]

I don't understand very much about such things, but I was intrigued by the same sentence, so I asked Larry. His reply was that the concept of "diamond buffer" is nothing proprietary to Larocco Audio, but that it merely describes a special type of circuit with a specific configuration of components.

The BUF 634 apparently uses that configuration "on a chip", i.e. integrated circuit. The thing that makes the Larocco Diamond Buffer special is the fact that it's made up of discrete components using the same basic idea of "diamond" configuration, but totally "maxed-out" in all respects. That's why it's larger and presumably sounds better than a chip.

Originally posted by Jap[size=large]Well, that is the very point: I am talking about the comparisons between PPL's maxed out PPA and the blockhead - not the typical PPA.[/size]

I just wanted to point out that the PPA at the Seattle meet, was not only a maxed out PPA with discrete diamond buffer but a maxed out PPA with discrete diamond buffer on steroids!! It was hooked up to LaRocco Audio's Labratory-Grade Power supply, which is quieter than running the amp off of batteries!! Dont underestimate the importance of running components off good power. Crap in, crap out.